Myelin is the insulating sheath surrounding nerve cells...

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          Axons with normal myelin               Demyelinated axons: Nerve impulse                                                                                                                                                     conduction slows or stops completely

Myelin is the insulating sheath surrounding nerve cells…the white matter coating our nerves, enabling them to conduct impuxlses between the brain and other parts of the body. It consists of a layer of proteins packed between two layers of lipids.

Myelin is produced by specialized cells: oligodendrocytes in the central nervous system, and Schwann cells in the peripheral nervous system. Myelin sheaths wrap themselves around axons, the threadlike extensions of neurons that make up nerve fibers. Each oligodendrocyte can myelinate several axons.

Myelin can be destroyed by hereditary neurodegenerative disorders such as the leukodystrophies, and by acquired diseases such as multiple sclerosis. Demyelinating diseases affect more than two million people worldwide.